1. Field of the Invention
The present invention relates generally to control valves, and, in particular, to control valves for use in connection with electronically-triggered flow valves and fluid control systems.
2. Brief Description of the Prior Art
In most fluid control systems, and more particularly, water conduit systems, control valves are utilized to control the flow of water through the piping system. Such control valves are commonly used in connection with electronic control centers, which contain sensor inputs to register a user""s request for operation of the flow valve. It is these valves, typically solenoid-operated valves that control the flow of water to the user. Such control valves have recently found great use in prison lavatory and water closet systems.
In the area of prison lavatory and water closet systems, there is a need for a method and apparatus for converting and controlling manually-operated prison lavatory flow valves, in particular, piston valves, which are operated by a user by depressing an external button connected to a rod. The rod is further connected to a lever on the mechanical valve. First and second chambers are separated by a flexible diaphragm or a piston, including O-ring seals. As the first chamber is filled by water, as supplied by the water inlet, the second chamber is filled by a tiny metering hole in the diaphragm or piston. The water outlet is connected to a lavatory spout or similar fixture. A tiny metering hole is the source that determines the time duration of the fluid flow. As the user depresses the button, the motion is communicated to the associated rod, and further moves a lever on the mechanical valve. As this lever is moved, the second chamber is relieved of the stored fluid, thus reducing the force holding the diaphragm or piston in the xe2x80x9coffxe2x80x9d position. The reduced force allows the first chamber to raise the flexible diaphragm or the piston, thereby disturbing the seal and further allowing fluid flow to occur through the outlet. The fluid flow continues as the first chamber fills the second chamber through the tiny metering hole. After the second chamber is filled, the diaphragm or piston is lowered into the original position and fluid flow stops.
The diaphragm, or, in the case of a piston flow valve, the piston, and the metering hole are required for the selected length of fluid flowing for the prisoner to wash hands, receive a drink, receive a shower, and the like. Due to the impurities in potable water, the tiny metering hole will often clog or be altered in size, causing the length of time to be insufficient or the length of time to be further extended, wasting water. This piston flow valve, and control valves associated with these types of flow valves, have numerous and separately functioning pieces. The assembly, maintenance, and repair of such a valve having many pieces is difficult, expensive, and time-consuming.
It is, therefore, an object of the present invention to provide a control valve having a minimum number of xe2x80x9cpieces,xe2x80x9d thereby reducing expense and maintenance cost. It is another object of the present invention to provide a control valve, which is simple in its installation and easy in its repair. It is a further object of the present invention to provide a control valve that does not require any significant plumbing alterations prior to its installation. It is a further object of the present invention to provide a control valve that is particularly adapted to retrofitting a piston flow valve.
Accordingly, the present invention is directed to a control valve that includes an adapter element having at least one adapter element fluid inlet and at least one adapter element fluid outlet. This adapter element is sealingly engaged with and in fluid communication with a piston flow valve. The piston flow valve, typically already present in the system, includes a piston flow valve fluid inlet and a piston flow valve fluid outlet. The control valve also includes a plunger mechanism sealingly engaged with and in fluid communication with the adapter element. The plunger mechanism has a plunger element in operable communication with the adapter element fluid outlet, such that the plunger mechanism may allow and disallow fluid flow through the adapter element fluid outlet. Further, the adapter element of the control valve is a unitary structure, consisting of only one unitary piece.